Project Summary The New York Center for Birth Defects Research and Prevention (NYCBDRP) proposes to continue its strong record of conducting epidemiologic research to identify the causes of birth defects through its participation in the Birth Defects Study to Evaluate Pregnancy exposureS II (BD-STEPS II). BD-STEPS II seeks to build on existing efforts to identify maternal exposures in early pregnancy that may increase the risk for having a pregnancy affected by certain major, structural birth defects. The NYCBDRP is well positioned to successfully implement BD-STEPS II. The NYCBDRP has been a major contributor to CDC's collaborative National Birth Defects Prevention Study (NBDPS) and the Birth Defects Study To Evaluate Pregnancy exposureS I (BD-STEPS I) since 1996. NYCBDRP researchers have already used NBDPS/BD-STEPS I data extensively to study the three main focus areas of BD-STEPS II: acute conditions such as infections; chronic conditions such as autoimmune disease, hypertension, and asthma; and medications to treat these conditions. The NYCBDRP has an experienced team in place to successfully implement all aspects of the proposed study: case and control ascertainment, clinical and contact information abstraction and review, subject recruitment, newborn bloodspot collection, linkages to state infectious disease surveillance systems, linkages to the New York State All Payer Database (APD) to validate self-reported medication use, and innovative epidemiologic investigations. The NYCBDRP research agenda will focus on expanding medication analyses using new BD-STEPS questions, developing analytic methods to identify risk factors for rare defects and patterns of co-occurring birth defects, and exploring the joint effects of chronic conditions and treatments on birth defect risk. The proposed pilot validation study will build on NYCBDRP subject matter expertise by focusing on antihypertensive medication use. Through a close relationship with the University at Albany School of Public Health, the NYCBDRP will continue to attract and mentor graduate-level students to conduct master's and dissertation projects using NBDPS/BD-STEPS data. From its position within the New York State Department of Health (NYSDOH), the NYCBDRP will leverage considerable NYSDOH resources through donated staff time, privileged access to individual medical records, the Congenital Malformations Registry, infectious disease surveillance systems, and the APD, and affiliation with the world-renowned Wadsworth Center laboratory for genetic studies.